title: Formation and segmentation of the vertebrate body axis.
abstract: Body axis elongation and segmentation are major morphogenetic events that take place concomitantly during vertebrate embryonic development. Establishment of the final body plan requires tight coordination between these two key processes. In this review, we detail the cellular and molecular as well as the physical processes underlying body axis formation and patterning. We discuss how formation of the anterior region of the body axis differs from that of the posterior region. We describe the developmental mechanism of segmentation and the regulation of body length and segment numbers. We focus mainly on the chicken embryo as a model system. Its accessibility and relatively flat structure allow high-quality time-lapse imaging experiments, which makes it one of the reference models used to study morphogenesis. Additionally, we illustrate conservation and divergence of specific developmental mechanisms by discussing findings in other major embryonic model systems, such as mice, frogs, and zebrafish.
authors.affiliation: Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), CNRS (UMR 7104), Université de Strasbourg, Illkirch F-67400, France; email: Pourquie@igbmc.fr.
authors.forename: Bertrand
authors.initials: B
authors.lastname: Bénazéraf
authors.forename: Olivier
authors.initials: O
authors.lastname: Pourquié
mesh_terms: D000818:Animals; D019521:Body Patterning; D047108:Embryonic Development; D006801:Humans; D009024:Morphogenesis; D054240:Primitive Streak; D015398:Signal Transduction; D014714:Vertebrates / Q000196:embryology* / Q000378:metabolism